/Engine/Source/Editor/BlueprintEditorLibrary/Public/BlueprintEditorLibrary.h
Replace any old operator nodes (float + float, vector + float, int + vector, etc) with the newer Promotable Operator version of the node. Preserve any connections the original node had to the newer version of the node.
static void UpgradeOperatorNodes ( [UBlueprint](API\Runtime\Engine\Engine\UBlueprint) * Blueprint )